Optical module structure

ABSTRACT

An optical module structure is provided. The optical module structure includes a holder, an elastic damper layer, and an optical component. The holder has an inner surface; the elastic damper layer is on the inner surface and has a trench at a first surface of the elastic damper layer; and the optical component is engaged with the elastic damper layer through the trench. Also, an optical system is provided. The optical system includes a light source, an, and a reflector, wherein a plurality of optical components in the optical module are arranged along a direction perpendicular to a direction of gravity.

FIELD

The present disclosure is related to an optical module structure and,more particularly, to an optical module structure that the weight of theoptical components thereof is borne by a tubular holder.

BACKGROUND

High resolution and high overlay accuracy have been required forsemiconductor process. For instance, the fabrication of integratedcircuits generally requires the formation of multiple integrated circuitstructures on a wafer or on one or more layers over the wafer. Thesestructures are frequently formed through a photolithography process,which may include a reticle through which ultraviolet light istransmitted to the wafer. The reticle blocks the light in areas of thewafer to remain unetched, and permits light to pass through areas to beetched.

Photolithography processes may further require metrology steps to ensureproper sizing and alignment of structures within a layer or betweenlayers. Metrology may not only be required to measure alignments on thewafer but also on the reticle. Generally, reticle metrology may becarried out separately from wafer metrology. The step and repeatalignment and exposure system is thus developed for achieving highresolution, high overlay accuracy and enhancement of the product yield.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are best understood from the followingdetailed description when read with the accompanying figures. It isnoted that, in accordance with the standard practice in the industry,various structures are not drawn to scale. In fact, the dimensions ofthe various structures may be arbitrarily increased or reduced forclarity of discussion.

FIG. 1A illustrates a cross-sectional view of an optical modulestructure according to some embodiments of the present disclosure.

FIG. 1B illustrates an optical module structure according to someembodiments of the present disclosure.

FIG. 2 illustrates a cross-sectional view of an elastic damper layeraccording to some embodiments of the present disclosure.

FIG. 3 illustrates a cross-sectional view of an elastic damper layeraccording to some embodiments of the present disclosure.

FIG. 4 illustrates a cross-sectional view of a holder and an opticalcomponent according to some embodiments of the present disclosure.

FIG. 5 illustrates a cross-sectional view of a holder and an elasticdamper layer according to some embodiments of the present disclosure.

FIG. 6 illustrates a cross-sectional view of an enlarged opticalcomponent and an elastic damper layer according to some embodiments ofthe present disclosure.

FIG. 7 illustrates a spread elastic damper layer according to someembodiments of the present disclosure.

FIG. 8A illustrates a cross-sectional view of a holder and a pluralityof elastic damper bulks according to some embodiments of the presentdisclosure.

FIG. 8B illustrates a cross-sectional view of an optical modulestructure according to some embodiments of the present disclosure.

FIG. 9 illustrates a cross-sectional view of an optical module structureaccording to some embodiments of the present disclosure.

FIG. 10 illustrates a cross-sectional view of an optical systemaccording to some embodiments of the present disclosure.

FIG. 11 illustrates a cross-sectional view of an optical modulestructure according to some embodiments of the present disclosure.

DETAILED DESCRIPTION

The following disclosure provides many different embodiments, orexamples, for implementing different features of the provided subjectmatter. Specific examples of elements and arrangements are describedbelow to simplify the present disclosure. These are, of course, merelyexamples and are not intended to be limiting. For example, the formationof a first feature over or on a second feature in the description thatfollows may include embodiments in which the first and second featuresare formed in direct contact, and may also include embodiments in whichadditional features may be formed between the first and second features,such that the first and second features may not be in direct contact. Inaddition, the present disclosure may repeat reference numerals and/orletters in the various examples. This repetition is for the purpose ofsimplicity and clarity and does not in itself dictate a relationshipbetween the various embodiments and/or configurations discussed.

Further, spatially relative terms, such as “beneath,” “below,” “lower,”“above,” “upper”, “on” and the like, may be used herein for ease ofdescription to describe one element or feature's relationship to anotherelement(s) or feature(s) as illustrated in the figures. The spatiallyrelative terms are intended to encompass different orientations of thedevice in use or operation in addition to the orientation depicted inthe figures. The apparatus may be otherwise oriented (rotated 90 degreesor at other orientations) and the spatially relative descriptors usedherein may likewise be interpreted accordingly.

As used herein, the terms such as “first”, “second” and “third” describevarious elements, components, regions, layers and/or sections, theseelements, components, regions, layers and/or sections should not belimited by these terms. These terms may be only used to distinguish oneelement, component, region, layer or section from another. The termssuch as “first”, “second”, and “third” when used herein do not imply asequence or order unless clearly indicated by the context.

The manufacture of integrated circuit devices involves repeatedsequences of the steps of deposition, photolithographic patterning, andetching. During the step of deposition, a layer of conductive orinsulating material is deposited on the surface of a semiconductorwafer. This material is then coated with a photosensitive resist. Duringthe step of photolithographic patterning, which includes a set ofoptical and chemical processes, images of some desired geometricpatterns residing on a reticle are transferred onto the photo resist.The semiconductor wafer is then developed and etched to remove materialfrom the areas exposed to light, corresponding to clear areas in thereticle images.

The primary tool used for projecting a circuit image from a reticle ontoa resist-coated wafer is the wafer stepper. That is, step and repeatalignment and exposure systems are employed in the processing ofsemiconductor wafers to form integrated circuits. Generally, large scaleintegrated circuits are often fabricated by utilizing a preciselycontrolled stage to successively position adjacent regions containing anintegral number of individual microcircuits on a semiconductor waferwith respect to an image of a reticle containing a next level of microcircuitry, wherein the image is formed by projection lenses of the stepand repeat alignment and exposure system.

This step and repeat printing operation forms an array of adjacentregions of micro circuitry on the semiconductor wafer in rows andcolumns in an ordered parallel and orthogonal manner. Successiveprocessing of the semiconductor wafer and printing of a further level ofmicro circuitry, aligned with the preceding processed regions to a highaccuracy, are typically employed in the fabrication of integratedcircuits from the semiconductor wafer. Successful alignment of thepreceding processed regions requires the use of an alignment system thatcan acquire alignment information from the semiconductor wafer and useit to position the precisely controlled stage so that the semiconductorwafer is properly aligned.

However, the alignment light source may be drifted to an incorrectposition due to optics displacement in some circumstances. Suchinstability of the alignment system would cause poor overlay accuracy,which may induce the electrical property of the semiconductor waferbecome poor. The optical components in the conventional optical modulesin the alignment system cannot be screw-fixed because the freedom ofmovement granted by the screw to the optical components is too high sothat the optical components may displace due to the vibration of theoptical modules under operation. Alternatively, the optical componentsin the conventional optical modules were fixed by adhesive at the edgethereof, thereby the weight of the optical components are borne by theadhesive and receive less freedom of movement than the screw. Thoseoptical components still may displace from the original positions due tothe aging of adhesive and thermal issues.

For example, in a conventional optical module, glue may be spread on aninner surface of a shell of the optical module in order to position theoptical components inside. The optical components are supported by theglue. However, the glue may not bear the weight of the opticalcomponents, particularly, the adhesion property of the glue may declineduring the alignment process due to the process temperature. As aresult, the glue itself may not only have aging issue but also theoptical component may have thermal expansion or contraction issues,which all may cause the optical components to become unbalanced ordisplaced in the optical module, or even dropped from the originalposition.

Accordingly, the present disclosure provide an optical module structurethat the optical component may be supported and positioned in theoptical module stably, thus the overlay accuracy may be enhanced and theyield of the integrated circuit devices may be improved.

Referring to FIG. 1A, an optical module structure 1 is provided. Theoptical module structure 1 includes a holder 10, an elastic damper layer20, and an optical component 30. The holder 10 has an inner surface 102.The elastic damper layer 20 is disposed on the inner surface 102. Insome embodiments, the elastic damper layer 20 has at least a trench 204at a first surface 202 of the elastic damper layer 20.

Referring to FIGS. 1A and 1B, FIG. 1A is a cross-sectional view of 1Balong line AB, and the holder 10 can be a hollow tube and may hold theobjects inside such as optical components 30. In some embodiments, theholder 10 has a tubular structure with an inlet end 104 and an outletend 106. In some embodiments, the holder 10 has a round cross section,an elliptical cross section, or a rounded rectangle cross section ingeometry for fitting the structures of the objects inside.

In some embodiments, the optical component 30 is disposed in the holder10 and thus be supported by the holder 10. That is, the weight of theoptical component 30 is borne by the holder 10. More precisely, in thepresent disclosure, the usage of the optical module structure 1 is in adirection that the inlet end 104 and the outlet end 106 of the holder 10are set horizontally. Meanwhile, the optical component 30 is erected onthe inner surface 102 (i.e., the angle C between the inner surface 102and the optical component 30 is about 90° in FIG. 1A) and a radialdirection of the optical component 30 is parallel to a direction ofgravity G as shown in FIG. 1A.

In order to apply the weight of the optical component 30 to the holder10, in some embodiments, the optical component 30 is in contact with theinner surface 102 of the holder 10. In some embodiments, an end point302 of the optical component 30 may in contact with the inner surface102, wherein the end point 302 belongs to a plain surface or a curvedsurface at an edge of the optical component 30.

In some embodiments, the optical component 30 is positioned by theelastic damper layer 20. Still referring to FIG. 1A, the opticalcomponent 30 is engaged with the elastic damper layer 20 through thetrench 204. In the present disclosure, the optical component 30 is notpositioned on the holder 10 through adhesives, instead, in someembodiments, the elastic damper layer 20 is made of an vibrationabsorption material so that the elastic damper layer 20 may absorb theshocks or the vibrations delivered to the optical component 30 and theholder 10, therefore the displacement of the optical component 30 may beavoided.

In some embodiments, the vibration absorption material may be rubber andthe like, including natural rubber and synthetic rubber. For instance,such vibration absorption material may be isobutylene isoprene rubber(IIR), thermoplastic rubber (TPR), ethylene propylene diene monomer(EPDM), chloroprene rubber (CR), hydrogenated nitrile rubber (NHBR)carboxylate nitrile rubber (XNBR), silicone rubber or high consistencyrubber (HCR). In some embodiments, some of the polymers with vibrationabsorption ability are also available, for example, polyurethane (PU) orthermoplastic polyurethane (TPU) are selectable material in making theelastic damper layer 20.

The optical component 30 may be a lens, an optical filter, and the like.The type of the lens may be various. For instance, the optical component30 may be a biconvex lens, a plano-convex lens, a positive meniscuslens, a negative meniscus lens, a plano-concave lens, a biconcave lens,or a combination thereof in the case of the optical module structureincludes multiple optical components 30. In some embodiments, theoptical component 30 may be a mask with at least a slit or aperture foroptical diffraction or interference usage. In some embodiments, theoptical component 30 is a lens or an optical filter which include aframe.

The end point 302 of the optical component 30 may be in contact with theinner surface 102. Accordingly, in some embodiments, referring to FIG.2, the thickness T1 of the elastic damper layer 20 at a bottom 204B ofthe trench 204 is about zero. Under such configuration, the weight ofthe optical component 30 previously shown FIG. 1A may be directly borneby the holder 10. In some embodiments, the elastic damper layer 20 isspaced between the optical component 30 and the inner surface 102 of theholder 10 at the bottom 204B of the trench 204, as will be discussed inFIG. 3.

Through the contact between the optical component 30 and the innersurface 102, the weight of the optical component 30 may not be borne bythe elastic damper layer 20, therefore the compression of the elasticdamper layer 20 may be avoided. Particularly, in the case of an opticalmodule structure that includes multiple optical components 30, thedifferent weights between different optical components 30 may inducedifferent extents of compression to the elastic damper layer 20, whichmay affect the alignment of the optical module structure. Moreprecisely, the heavier the optical component 30, the greater loadbearing on the elastic damper layer 20. As a result, an optical centerof the optical component 30 may deviate from a central axis of theholder 10.

Referring to FIG. 3, in some other embodiments, the thickness T2 of theelastic damper layer 20 at a bottom 204B of the trench 204 is largerthan zero, which means the optical component 30 may be spaced from theinner surface 102 of the holder 10 by the elastic damper layer 20. Underthis configuration, the weight of the optical component 30 may beindirectly borne by the holder 10. In such embodiments, the bearingloads may be applied to the elastic damper layer 20, and while theoptical component 30 is engaged with the elastic damper layer 20 throughthe trench 204, the thickness of the bottom 204B of the trench 204 mayslightly decrease due to compression. In the case of an optical modulestructure 1 includes multiple optical components 30, such thicknessdecrease may be neglected if the weights of the optical components 30are substantially the same.

Referring to FIG. 4, in some embodiments, the holder 10 has a tubularstructure so that the optical components 30 may in contact with theinner surface 102 at a plurality of points or at a circumferencethereof. In some embodiments, the inner diameter D_(H) of the holder 10is substantially equal to a diameter D_(L) of the optical component 30.That is, the size of the lens disposed in the holder 10 may be identicalto the inner space of the holder 10.

Referring to FIG. 5, in some embodiments, the holder 10 includes atleast a protrusion 108 on the inner surface 102. The protrusion 108 isintegrated with a main body 10 a of the holder 10 and the material ofthe protrusion 108 is identical to the main body 10 a. In someembodiments, the protrusions 108 are at the inlet end 104 and the outletend 106 of the holder 10 and thus encloses an area F for disposing theelastic damper layer 20. In some embodiments, the thicknesses of theprotrusions 108 are consistent with each other. In some embodiments, thethickness of the elastic damper layer 20 is less than or identical tothe thickness of the protrusion 108. In some embodiments, the topsurface 108 a of the protrusion 108 is substantially coplanar with thefirst surface 202 of the elastic damper layer 20, therefore a light pathof the holder 10 may not be blocked or affected by the elastic damperlayer 20.

In the present disclosure, the weight of the optical component 30 isborne by the holder 10, and the elastic damper layer 20 may devise theoptical component 30 at an adequate position on the inner surface 102 ofthe holder 10. Referring to FIG. 6, in some embodiments, an edge portion304 of the optical component 30 is laterally surrounded by the elasticdamper layer 20, thus the optical component 30 may not be laterallydisplaced in the holder 10. In some embodiments, the thickness of theelastic damper layer 20 is not only less than or identical to thethickness of the protrusion 108 as foregoing mentioned, but also notless than half of the thickness of the protrusion 108 in order toprovide enough resisting capacity to lateral force generated byvibration.

Referring to FIG. 7, in some embodiments of the present disclosure, thevibration absorption material in the holder may have a film structure 20a with multiple trenches 204 for the optical components engagedtherewith. Such film structure 20 a may be manufactured by forming thetrenches on a smooth surface of an unprocessed film, and then theprocessed film is spread on the inner surface of the holder. In somealternative embodiments of the present disclosure, the vibrationabsorption material in the holder may be separated as a plurality ofunits at the very beginning in the manufacturing process.

Referring to FIGS. 8A and 8B, in some embodiments, a plurality ofelastic damper bulks 206 may be disposed at the inner surface 102 of theholder 10, and a plurality of optical components 30 may be disposed inthe holder 10 by engaging with the plurality of elastic damper bulks206. The elastic damper bulks 206 are vibration absorption units whichmay be made by rubber and the like, including natural rubber andsynthetic rubber. The material for forming the elastic damper bulks 206may be isobutylene isoprene rubber (IIR), thermoplastic rubber (TPR),ethylene propylene diene monomer (EPDM), chloroprene rubber (CR),hydrogenated nitrile rubber (NHBR) carboxylate nitrile rubber (XNBR),silicone rubber or high consistency rubber (HCR). In some embodiments,some of the polymers with vibration absorption ability are alsoavailable, such as polyurethane (PU) and thermoplastic polyurethane(TPU).

In some embodiments, each of the elastic damper bulks 206 may include aconcave sidewall 206 a, a convex sidewall 206 b, or a vertical sidewall206 c. The curvature of the concave sidewall 206 a may correspond to thecurvature of an adjacent biconvex lens, plano-convex lens, positivemeniscus lens, or negative meniscus lens. The convex sidewall 206 b maycorrespond to the curvature of an adjacent positive meniscus lens,negative meniscus lens, plano-concave lens, or biconcave lens. Thevertical sidewall 206 c may against the plain surface of an adjacentplano-convex lens, plano-concave lens, or optical components withvertical sidewall. The elastic damper bulks 206 may be manufactured anddisposed in the holder individually. For instance, the elastic damperbulks 206 and the optical components 30 may be arranged along adirection perpendicular to the direction of gravity G alternatively,that is, the elastic damper bulks 206 and the optical components 30 maybe arranged from the inlet end 104 or the outlet end 106 of the holder10 one by one, and vice versa.

Referring to FIG. 9, in some embodiments, the holder 10 may be separatedinto a first section 10 a and a second section 10 b. In someembodiments, the diameter of the first section 10 a is different fromthe diameter of the second section 10 b. The connection of the firstsection 10 a and the second section 10 b can take various forms, forexample, the first section 10 a and the second section 10 b may beintegrated or be connected with screw connection. In some embodiments,the vibration absorption material in the first section 10 a and thesecond section 10 b may be used in different types. For example, thereis an elastic damper layer 20 on the inner surface 102 at the firstsection 10 a, whereas the inner surface 102 at the second section 10 bhas a plurality of elastic damper bulks 206 thereon as shown in thefigure. Moreover, both of the thicknesses of the elastic damper layer 20and the elastic damper bulks 206 are also not higher than the thicknessof the protrusions 108 on the inner surface 102. In some embodiments,the first surface 202 of the elastic damper layer 20 or the top surface206 a of the elastic damper bulks 206 may coplanar with the top surface108 a of the protrusion 108 proximity to the inlet end 104 or the outletend 106.

The optical module structure provided in the present disclosure may beused in an optical system. Referring to FIG. 10, in some embodiments,the optical system includes a light source 40, an optical module 1 a,and a reflector 50. The light source 40 is disposed in proximity to aninlet end 104 of a holder 10 of the optical module 1 a. The details ofstructure of the holder 10 may refer to previous shown FIG. 9. The lightsource 40 may provide a light L to the holder 10, such as laser. Thereflector 50 is aligned with the optical module 1 a and may change adirection of the light L. In some embodiments, when the optical module 1a and a target wafer 70 are arranged horizontally (i.e., an axialdirection of the optical module 1 a is perpendicular to a direction ofgravity G), the direction of the light L propagating along the axialdirection of the optical module 1 a can be altered by a reflector 50 infront of an outlet end 106 of the holder 10. In some embodiments, anangle K between a horizontal extension of the holder 10 and thereflector 50 is about 135°, thereby the angle of reflection of the lightL may be about 90°. The reflector 50 is made of a material which has areflectivity of greater than 90%. In some embodiment, a thin silver filmcoated onto a thin glass film is suitable for making the reflector 50.

In some embodiments, the optical system includes a susceptor 60 at alower stream of the reflector 50, wherein a top surface 602 of thesusceptor 60 is parallel to the inner surface 102 of the holder 10.Accordingly, the target wafer 70 over the susceptor 60 is parallel tothe inner surface 102 of the holder 10, and meanwhile, target wafer 70is perpendicular to the light L. In some embodiments, the susceptor 60may be a pedestal, a wafer chuck, and/or other suitable wafer holdingapparatus.

Referring to FIG. 11, in some embodiments, the holder 10 is set with adirection parallel to the direction of gravity G. under suchconfiguration, because the optical components 30 inside the holder 10are arranged along a direction parallel to the direction of gravity G,the weight of the optical components 30 is borne by the elastic damperlayer 20 instead of the holder 10. In other words, the stableness of theoptical components 30 depends on the features of the elastic damperlayer 20. In some embodiments, the trenches 204 are U-shaped so thatedge portions 304 of the optical components 30 may be engaged with theelastic damper layer 20 and the weight of the optical components 30borne by the elastic damper layer 20.

In some embodiments, a width of the trench 204 at the first surface 202a is equal to or larger than a width of the optical component 30, inorder to ensure the optical component 30 may be engaged with the elasticdamper layer 20. In some embodiments, in consideration for theelasticity of the elastic damper layer 20, the size of the edge potion304 of the optical component 30 may be larger than the size of theU-shaped trench 204 slightly, thus the elastic damper layer 20 maybetter support the edge potion 304 of the optical component 30 andtherefore obtain better stableness of the optical component 30.

In the present disclosure, an optical module structure which rotates thedirection of the optical components by 90° is provided. The purpose ofthe rotation is to use an outer shell of the optical module as a holderto bear the weight of a plurality of optical components in the opticalmodule. In addition, the optical components are positioned by an elasticdamper layer or a plurality of elastic damper bulks so that the opticalcomponents in the holder may not be displaced under vibration. In somealternative embodiments, the optical components arranged to align alongthe direction of gravity is provided. The elastic damper layer or theelastic damper bulks still may provide enough elasticity to hold theoptical components. Based on the present disclosure, the optical modulefor alignment may avoid optics displacement, therefore the overlayaccuracy may be enhanced.

In one exemplary aspect, an optical module structure is provided. Theoptical module structure includes: a holder, an elastic damper layer,and an optical component. The holder has an inner surface. The elasticdamper layer is on the inner surface and has a trench at a first surfaceof the elastic damper layer. The optical component is engaged with theelastic damper layer through the trench.

In another exemplary aspect, an optical module structure is provided.The optical module structure includes: a holder, a plurality of elasticdamper bulks, and a plurality of optical components. The holder has aninner surface. The elastic damper bulks are at the inner surface. Theoptical components are in the holder by engaging with the elastic damperbulks.

In yet another exemplary aspect, an optical system is provided. Theoptical system includes: a light source, an optical module, and areflector. The light source is configured to provide a light. Theoptical module is aligned with the light source and configured toreceive the light. The optical module includes a holder, an elasticdamper layer, and a plurality of optical components. The holder has aninner surface. The elastic damper layer is on the inner surface of theholder and has a plurality of trenches at a first surface of the elasticdamper layer. The optical components are engaged with the elastic damperlayer through the trenches. The reflector is aligned with the opticalmodule and configured to change a direction of the light. The opticalcomponents are arranged along a direction perpendicular to a directionof gravity.

The foregoing outlines structures of several embodiments so that thoseskilled in the art may better understand the aspects of the presentdisclosure. Those skilled in the art should appreciate that they mayreadily use the present disclosure as a basis for designing or modifyingother processes and structures for carrying out the same purposes and/orachieving the same advantages of the embodiments introduced herein.Those skilled in the art should also realize that such equivalentconstructions do not depart from the spirit and scope of the presentdisclosure, and that they may make various changes, substitutions, andalterations herein without departing from the spirit and scope of thepresent disclosure.

1. An optical module structure, comprising: a holder having an innersurface; an elastic damper layer on the inner surface and having atrench at a first surface of the elastic damper layer; and an opticalcomponent engaged with the elastic damper layer through the trench, theoptical component having a first optical surface and a second opticalsurface opposite to the first optical surface, and the first opticalsurface and the second optical surface are both in contact with theelastic damper layer.
 2. The optical module structure of claim 1,wherein a thickness of the elastic damper layer at a bottom of thetrench is about zero.
 3. The optical module structure of claim 2,wherein the optical component is in contact with the inner surface ofthe holder.
 4. The optical module structure of claim 1, wherein an innerdiameter of the holder is substantially equal to a diameter of theoptical component.
 5. The optical module structure of claim 1, whereinthe elastic damper layer is spaced between the optical component and theinner surface of the holder at a bottom of the trench.
 6. The opticalmodule structure of claim 1, wherein a material of the elastic damperlayer comprises rubber.
 7. The optical module structure of claim 2,wherein the holder further comprises a protrusion on the inner surface.8. The optical module structure of claim 7, wherein a top surface of theprotrusion is substantially coplanar with the first surface of theelastic damper layer.
 9. An optical module structure, comprising: aholder having an inner surface; a plurality of elastic damper bulks atthe inner surface; and a plurality of optical components in the holderby engaging with the plurality of elastic damper bulks, each of theoptical components having a first optical surface and a second opticalsurface opposite to the first optical surface; wherein an edge portionof each of the optical components is in contact with the inner surfaceof the holder, and the first optical surface and the second opticalsurface are in contact with the plurality of elastic damper bulksadjacent to the edge portion.
 10. The optical module structure of claim9, wherein the optical components comprise a concave lens and a convexlens.
 11. The optical module structure of claim 9, wherein the opticalcomponents are arranged along a direction perpendicular to a directionof gravity.
 12. The optical module structure of claim 9, wherein theholder further comprises a first section and a second section, and adiameter of the first section is different from a diameter of the secondsection.
 13. The optical module structure of claim 9, wherein theelastic damper bulk comprises a concave sidewall or a convex sidewall.14. An optical system, comprising: a light source configured to providea light; an optical module aligned with the light source and configuredto receive the light, comprising: a holder having an inner surface; anelastic damper layer on the inner surface of the holder and having aplurality of trenches at a first surface of the elastic damper layer;and a plurality of optical components engaged with the elastic damperlayer through the trenches, each of the optical components having afirst optical surface and a second optical surface opposite to the firstoptical surface, and the first optical surface and the second opticalsurface are both in contact with the elastic damper layer; and areflector aligned with the optical module and configured to change adirection of the light; wherein the optical components are arrangedalong a direction perpendicular to a direction of gravity.
 15. Theoptical system of claim 14, wherein the optical component is spaced fromthe inner surface of the holder by the elastic damper layer.
 16. Theoptical system of claim 14, wherein an angle between the holder and thereflector is about 135°.
 17. The optical system of claim 14, wherein oneof the trenches engaged with the optical component is U-shaped andhaving an opening facing an inner side of the holder from across-sectional view.
 18. The optical system of claim 14, wherein amaterial of the elastic damper layer is isobutylene isoprene rubber. 19.The optical system of claim 14, further comprising a susceptor at alower stream of the reflector, wherein a top surface of the susceptor isparallel to the inner surface of the holder.
 20. The optical system ofclaim 14, wherein the light source comprises laser.